I have to replace the shaft on my distributor . The tach gear drive has broken teeth. Has anyone done this that can give any tips before i tear into this???

Just that you mark the position of the distributor body in relation to the engine, and the position of the rotor in relation to the distributor body. This will save the pain of having to re-time it completely when you put it back together. Don't forget to dig all the dried out grease out of the grease well and replace it with fresh moly grease. Actually, you don't necesarily need to replace the shaft. The gear is attached to the shaft with a roll pin, which you knock out with a punch. GM still sells the shaft assemblies, if you have to buy the whole thing. I'd wait to see how much wear there is on the shaft before replacing it.

pulling the dist out and replacing it is the easy part. was womdering about the shaft itself. thanks for the tip on just replacing the tach drive gear on the shaft, thats the problem i wast to address. just have to find a new gear now.

Only the lower drive gear comes off the shaft,and that you have to do to remove the shaft from the housing. The tach gear is part of the dist. shaft and requires the replacement of the complete shaft. While you have it apart you must also check the condition of the upper and lower bushings for wear,along with checking the breaker plate for looseness on the upper shaft. If there is a loose fit the plate will move and cause the dwell to change which means your timing will change. That means the car runs badly. The other area you need to check is the small tach shaft. It can be worn,or more than likely the small bushing it rests against is gone. The bronze threaded housing the small shaft sits in can be worn. If these areas are not addressed, you WILL be changing your main shaft again,SOON! So be very thorough,or have someone who is familiar with this dist. go over it for many more years of trouble free service. Good Luck! John

Hi
I'm in process of doing this.
My main shaft was very worn at the lower bushing.
I ordered both, the bushing and tach drive shaft from TLD Corvette together with some small parts, like shims.
I also modified the cast distributor housing with a pressure lubrication hole in the lower galley to lubricate the lower bushing and a .030 hole through the lower flange to spray pressure oil onto the drive gears.
This to eliminate the extra wear caused by the high volume oil pump of my big block.
I will also order Lars's recurve kit and install the PETRONIX kit to get writ of the points.
I do have slight problems to find a .460 reamer for the lower bushing. What a stupid size !!

Good luck Gunther

Hi,

I did this last year. I started off trying the re-bush myself, but the kit didn't fit the old housing. Turns out that machining is required. I took it to a local corvette shop that had had the tools needed. Cost $95 plus kit. This was not one for the garage.

Alex